[anandpadhye]

Originally Posted by tsk1979

As for manual transmission, pressing clutch disengages clutch. Clutch wear happens when clutch is slipping. Fully disengaged, there is no cluch plate wear.

Sure, I would expect the DSG to shift to N on it's own if required and the driver should not have to worry about doing it.

But, DSG is a clutch based AT, so it definately has to slip the clutch (during take off, etc), I do not think there is any other way it can work.
With DSG, how can you come to a complete halt or even crawl at 2/3 kmph without (DSG automatically) slipping the clutch for you???

[tsk1979]

Originally Posted by anandpadhye

Sure, I would expect the DSG to shift to N on it's own if required and the driver should not have to worry about doing it.

But, DSG is a clutch based AT, so it definately has to slip the clutch (during take off, etc), I do not think there is any other way it can work.
With DSG, how can you come to a complete halt or even crawl at 2/3 kmph without (DSG automatically) slipping the clutch for you???

You cannot.
Yet in a real world traffic jam with crawl speeds, your car has to function. As a user why should I car what is the tech.
I bought an automatic car, and it will be used like an automatic car, like all over the world. You cannot ask a customer to drive an automatic like a manual.
Why is it that only skoda automatics have such high rates of failure?

This driving condition thing is they way of moving attention away from poor engineering or QC

[gthang]

Originally Posted by tsk1979

If you are going to drive an automatic like a manual(shift to neutral and D continuosly), why spend more on an automatic, might as well buy a manual.
Automatics have always been driven like this.
As for manual transmission, pressing clutch disengages clutch. Clutch wear happens when clutch is slipping. Fully disengaged, there is no cluch plate wear.

Originally Posted by tsk1979

I bought an automatic car, and it will be used like an automatic car, like all over the world. You cannot ask a customer to drive an automatic like a manual.

Pardon my (and probably VW's) ignorance in assuming that an owner/driver of a DSG equipped car would know the difference between a torque converter automatic and a dual clutch gearbox akin to how one would expect an owner/driver to know if the vehicle is FWD or RWD.

It would have been convenient if they would have incorporated a stop sensor to switch to neutral, but in my humble opinion, I feel it would go against the quick shift and gear pre selection core ideas. I also dont feel its asking too much to shift between neutral and drive for the performance and other plus points it has over a conventional torque converter automatic. But that's just me

Cheers.

[tsk1979]

Originally Posted by gthang

Pardon my (and probably VW's) ignorance in assuming that an owner/driver of a DSG equipped car would know the difference between a torque converter automatic and a dual clutch gearbox akin to how one would expect an owner/driver to know if the vehicle is FWD or RWD.

It would have been convenient if they would have incorporated a stop sensor to switch to neutral, but in my humble opinion, I feel it would go against the quick shift and gear pre selection core ideas. I also dont feel its asking too much to shift between neutral and drive for the performance and other plus points it has over a conventional torque converter automatic. But that's just me

Cheers.

Are DSG cars failing all over the world. If they were, your argument would be true. Somehow, they fail in India quite a bit more. Moreover, failure of DSG is happening more in one type of DSG(I think petrol) rather than diesel.
So if your argument is correct, then all DSGs should be seeing high failure rate, not just the petrol ones.

[anandpadhye]

Originally Posted by tsk1979

You cannot.
Yet in a real world traffic jam with crawl speeds, your car has to function. As a user why should I car what is the tech.
I bought an automatic car, and it will be used like an automatic car, like all over the world. You cannot ask a customer to drive an automatic like a manual.
Why is it that only skoda automatics have such high rates of failure?

This driving condition thing is they way of moving attention away from poor engineering or QC

Absolutely.

The buyer of automatic car should not have to care about all this at all. But Skoda is not claiming that one has to care about it. They are not saying that driving conditions or driving styles are the culprit.

As far as the technical reasoning behind the failures, according to me the reason for higher failure rate of DSG (versus regular torque convertor based AT) lies in this fact - DAG is a clutched AT - it slips the clutch whenever it has to and the long term reliability of this technology is a problem (as of now). This does not mean this technology has no future. I am sure this will be resolved in the long run - like most of the engineering challenges are overcome in the world. But it also does not mean that Skoda should use customer cars for testing...


So it depends on what's the purpose of this thread:
Blame it on drivers? - No way.
Vindicate drivers? - Well, who is blaming them anyway?
Discuss reason for DSG failures? - Sure, for that it must be mentioned and understood that DSG different from torque convertors.

[gthang]

Originally Posted by tsk1979

Are DSG cars failing all over the world. If they were, your argument would be true. Somehow, they fail in India quite a bit more. Moreover, failure of DSG is happening more in one type of DSG(I think petrol) rather than diesel.
So if your argument is correct, then all DSGs should be seeing high failure rate, not just the petrol ones.

I thought this thread already highlighted the fact that DSG failure is a global phenomenon. Also the fact that the different architecture of the 6 vs 7 speed amplifies the failure cause.

Imagine a scenario where a driver who is only used to current generation softroaders with all wheel drive gets into a manual transfercase 4x4, and thinks that it is OK to drive in 4WD mode all the time. Would ensuing failure be considered manufacturing defect? No. It would be attributed to Driver Awareness (lets call it I), or, Driver Ignorance (lets call it Q).

Now, VW obviously used a value too high/low for the I/Q quotient in their calculations. Now, when failures arise, it does not sound nice when VW says that it is due to lack/abundance of I/Q that it happens. Nobody likes to hear that.

Sure, it's easier to carpet bomb Skoda (VW) rather than sniping out the root cause.

Cheers.

[Sutripta]

I believe the failures are in the 'mechatronic' unit, not the clutches.

Regards
Sutripta

[gthang]

Originally Posted by Sutripta

I believe the failures are in the 'mechatronic' unit, not the clutches.

Regards
Sutripta

Are the two components related?

Cheers.

[tsk1979]

Originally Posted by Sutripta

I believe the failures are in the 'mechatronic' unit, not the clutches.

Regards
Sutripta

Thanks for the clarification. I do not see a reason for this component to be affected by stop and go traffic. Looks more to be a design flaw.

[Sutripta]

Originally Posted by gthang

Are the two components related?

Cheers.

You tell me!

Regards
Sutripta

[vina]

Originally Posted by tsk1979

...

Why is it that only skoda automatics have such high rates of failure?

This driving condition thing is they way of moving attention away from poor engineering or QC

I guess by Skoda automatics you mean VW DSG.

By the way, DSG technology is not completely unique to VW, other manufacturers have it too (they don't call it DSG) and they are not facing as many problems to my knowledge.


On your (tsk's) comment on another post - yes DSG is failing all over the world. There were two major recalls in US a few years ago.

On your comment on Mechatronics in stop and go traffic - mechatronics has to work harder (the "Mechatronics" unit does what your and my knee and hand do - disengage the clutch, shift the gears, rengage the clutch) in stop and go traffic. Most likely this is an endurance failure of the components involved.

[anandpadhye]

Originally Posted by vina

On your comment on Mechatronics in stop and go traffic - mechatronics has to work harder (the "Mechatronics" unit does what your and my knee and hand do - disengage the clutch, shift the gears, rengage the clutch) in stop and go traffic. Most likely this is an endurance failure of the components involved.

I second that.
It's a durability issue rather than a design one.


And why Skoda has the higher (or highest) rate of DSG failure (compared to VW/Audi, etc)? - because Skoda sells highest numbers of DSG cars in India .

[sridhar-v]

Originally Posted by V-16

MAybe the DSG unit is not tropicalised but then again, why not. And that does not seem to be the reason because these dsg units are failing on all their cars all over, VW, Audi, Skoda, you name it.

I remember one fact from my days of reverse engineering defense equipment. Tropicalisation is a necessary fact of life for India. There were 2 main areas we noticed:-

1. Rubber & composites grades (not much of palstics used then. But I guess it applies to them also). If your primary application is going to be based in very cold temperatures you need a seperate grade of rubber. You cannot use this grade in a tropical country like ours as @ 35-45 degC it will become very soft & loose its sealing/damping properties. In our defence environment we have the deserts & the Siachen front. Equipment needs to be serviced & many parts changed before moving from one to another. Hell even the British delayed their counterattack at El-Alamien ( during WW2) by a few weeks to render their newly supplied tanks & artillery suitable for desert use.

2. The same applies to the base materials also. A particular grade of steel will snap like a twig in the Nort Euorpe/Siberian winters but carry on merrily in our climate. And the grade suitable for Arctic winters will have strength limit problems here. This is of course at the extreme loading conditions, BUT I AM GIVING THESE EXAMPLES JUST TO ILLUSTRATE THE COMPLEXITIES INVOLVED.

A classic example of such issues is the Space Shuttle failure (on launch) due to rupture of the sealing O-rings in the Solid State Boosters. ( Happened due to exposure to a Storm before launch).


I suspect something like this is happening with all the german brands - refer to complaints re electronics failures, wiring dying due to moisture & coming back to life after the rains stop etc.

Possibly the volumes in India do not justify the minor reworks required to solve these problems. Or they just do not care as they are getting away charging a hefty premium.

[Swanand Inamdar]

So, all in all Mechatronics have a high chance of failures. Skoda's DSG at that. Why? Because Skoda sells more cars in India, than VW or Audi. Hence, the fact that Skoda DSG's fail.

My question is- If we are driving the DSG's wrong, then whats the proper way to drive it? Am I supposed to shift to N at complete halts, or let the DSG do its thing, while I just press the brake?

[SPIKE ARRESTOR]

Hi Guys,

Any idea what is failing? There are reports that "It is failing, it is failing" but what exactly is "It" ? Any pics? Also any inputs on the failure rates (B10, L90 etc) ?

I was a Vehicle Test Engineer with an Indian company. We sell products in many countries including Uganda and Rwanda , if we were unable to simulate a real world usage pattern (ambient, driving cycle) here in India, we made sure it was tested in the country where it is likely to be sold or has market scope. Hence, I do not buy the statement regarding "Indian conditions" !

Spike